Multicylinder ignition generator



Patented Dec. 23, 1941 MULTICYLINDER IGNITION GENERATOR William D.Crocker, Springfield, Mass., assignor to American Bosch Corporation,Springfield, Mass., a corporation of New York Application December 14,1940, Serial No. 370,103

(Cl. 17l-2(i9) 4 Claims.

The present invention relates to multicylinder ignition generators forinternal combustion engines, such as magnetos and timer distributorsassociated with battery ignition coils, and it relates particularly tosuch a. generator with a distributor having a housing of metal orinsulating or other material acting as a radio shield or a dust or watercover for the distributor plate or cap of the generator.

The primary object of the invention is to provide in a generator of thiskind a distributor having a housing which is directly and detachablyfastened to the generator frame and to which the distributor plate isinteriorly and positively fastened detachab'ly and solely, so that thetwo elements are removable from and attachable to the generator frame asa unit only and only when so removed from the generator may be attachedto and detached from each other. Preferably, the distributor platehousing carries outlet terminals or other means for the sparkplug cablespassing individually therethrough from electrical connection with thedistributor plate, and has a detachable end wall or other portion whichmay be removed Whenever the ignition generator is at rest, whether ornot installed on the engine, in order that the distributor plate may bedetached from the housing, and/or in order that sparkplug cables may bemore readily disconnected from the distributor plate. In such preferredconstruction, that wall or portion, in the form of a flanged plate, isso arranged as to be detached from or attached to the remainder of thehousing, as a rim surrounding th distributor plate, by means of the samescrews as fasten the housing to the generator frame. In this way, asimple, inexpensive, positively connected and compact arrangement isprovided in a construction which meets the re quirements for quick andready assembly and disassembly, for inspection, adjustment or repair ofthe generator while on or off the engine, and furthermore comprisingparts which are positively fastened together so as to remain securelyand dependably fastened under severe conditions of vibration as on anairplane.

Another object of the invention is to provide a distributor platehousing which may or may not have the detachable arrangement above notedbut which is provided with a timing window, and a movable door forsealing it, in registry with a timing window in the distributor plate.

Other objects and advantages of the invention will appear from thefollowing description taken in. connection with the accompanying drawingshowing, as an example, a metal housing acting with the metal frame of amagneto to constitute therewith a complete radio shield for thegenerator, and having individual outlets for the respective shieldedsparkplug cables. In the drawing,

Fig. l is an elevation of the rear end of the magneto showing thepreferred form of the housing, with some interior parts of theassociated distributor plate and sparkplug cables shown in broken lines;Fig. 2 is a fragmentary section, partly in elevation, on line 22 of Fig.l; and Fig. 3 is a top plan View of the housing in place on the magneto,with certain interior parts shown in broken lines.

In the drawing, the reference numeral I generally indicates a magnetoframe of die cast metal enclosing an ignition coil 2, magnetic rotor 3,distributor gearing 4 and distributor rotor 5 electrically connected tothe high tension terminal 6 of the coil, all of the general form shownin Patent No. 2,243,418. The frame I has three outwardly-extendingthreaded lugs like 1 into which extend the three screws 8 to fastenthereto as a unit over the open rear end of the frame, as willhereinafter appear, the Bakelite distributor plate 9 and the metalhousing therefor generally indicated by ID. The distributor plate has onits interior face the circularly arranged electrodes H, which arecooperative sequentially with the distributor rotor 5 to form a jumpspark distributor, and which are electrically connected by metal insertsto the sockets of the sparkplug cable outlets l2 accessible at theexterior face of the distributor plate, all as well known. The housingIt comprises a die cast metal rim [3 of generally rectangular form openat opposite ends and fitting against the open end of the frame I aroundthe distributor plate 9. This rim has an inturned flange l4 to which thedistributor plate 9 is positively and detaehably fastened by screws I5interiorly of the housing Hi, and three sockets l6 aligned with thethreaded openings in lugs 1. Fitted over the rear opening of the rim isa sheet metal cover plate I! with a peripheral lip [8, which plate isdetachably fastened to the rim by the same screws 8 as detachably fastenthe housing [0 to the magneto frame I exteriorly of the housing. Thisfastening arrangement, as in the case of the arrangement for fasteningthe distributor plate 9 to the housing, is of the well known kind inwhich the screw has a threaded end portion and a shank of reduceddiameter whereas both ends of the engaging members are threaded, so thatthe screw can be detached completely if desired but is normally retainedloosely to prevent loss when the members are detached. To assure readyand accurate alignment of the members when assembled, the inturnedflange I4 carries two diagonally opposite dowel pins I9 arranged toextend loosely into registering holes in the inner face of .theperipheral rim of the distributor plate 9, and the magneto frame Icarries two alternate dowel pins 20 arranged to extend loosely intoregistering holes in the flange I4. The distributor plate has the usualtiming window 2i and the cover plate I] has a registering windownormally sealed by a tightly fitting pivoted metal door 22, whereby thedistributor gearing t may be timed in known manner and whereby the radioshielding is not reduced in effectiveness during operation of themagneto. 'Individual metal outlets 23 of known kind are fastened to therim i3 directly over the distributor plate sockets i2. Each outlet is soconstructed that when tightly screwed together, after the end connectorterminal 2d of the cable is pushed into its socket I2, it grips itsshielded sparkplug cable 25, and when loosened it allows the cable to bepulled or pushed therethrough in attaching or detaching the connectorterminal to or from the socket.

' lhe disassembly and assembly as a unit of the distributor plate 9 andits housing In to and from the magneto frame I, and with respect to eachother, will now be described. With the assembly as shown in the drawing,whether on or off the engine, assume that the magneto is to be serviced.The three screws 8 are backed out of threaded engagement with the lugsI, whereupon the housing I0, with the distributor plate 9 fastenedthereto and the sparkplug cables fastened in the outlets 23 inelectrical connection with the sockets I 2 of the distributor plate, isdetached as a unit from the magneto frame I. The internal parts of themagneto and the inner face of the distributor plate 9 are then exposed.If now the screws 8 are backed completely out of sockets I6, the coverplate II may be taken off the rim I3 to give access to the outer face ofthe distributor plate. The sparkplug cables 25 may then be detached fromthe distributor plate after loosening the outlets 23, and thedistributor plate 9 may then be detached from the rim I3 after thescrews I5 are disengaged from the inturned flange I4. The assembly ofthe distributor plate 9 and housing It to the magneto will now beunderstood. However, it is noted that the sparkplug cables 25 are morereadily connected either when the distributor plate is out of thehousing or when it is fastened to the rim I3 but the cover plate I! isoff. Also it is noted that the magneto timing can be observed'with thehousing I0 attached to the frame, mereby by swinging the door 22 toexpose the timing windows.

It will be observed that when the housing I0 is assembled to the frame Iand the door 22 is closed, the magneto is completely shielded againstthe emanation of radio waves from within and against the entry of dustand water from without. By having the housing Ill and distributor plate9, together with the sparkplug cables when connected, detachable as aunit from the frame I by fastening the plate and the cable outlets tothe housing solely, the internal parts of the magneto may be exposedquickly after merely backing out the three screws 8 from engagement withth lugs I; and by providing the detachable cover plate II, the outerface of the distributor plate 9 may be exposed by removing those screwsto thereby facilitate the connection of the sparkplug cables 23, whetherthe rim I3 is off or loosely on the frame I, and also to detach thedistributor plate from the rim I3 by backing out the four screws I5.Furthermore by providing the lugs I exteriorly of the frame andextending the flange I4 inwardly, the same distributor plate 9 may beused with the same frame I, with the lugs I removed if desired, butwithout a housing I0, merely by using longer screws I5 extending intothreaded lugs inside the frame. In this connection, it will beunderstood that the dowel pins I9 and 20 assist in locating thedistributor plate electrodes II in accurate gap relationship with thedistributor rotor 5 notwithstanding the interposition therebetween ofthe rim I3, and that the same dowel pin openings in the distributorplate may be used for dowel pins, but longer than I9, extending from theframe I when the housing I0 is not used.

Although but one embodiment is described specifically herein, it will beunderstood that many changes may be made, and many variations may beincorporated, without departing from the invention as broadly expressedin the appended claims. For instance, the magneto may be designed forany other suitable number of sparkplugs and may be of any typeincorporating any form of distributor with a plate having any form ofsparkplug cable connection thereon in any suitable arrangement. If thehousing is not to act as a radio shield as well as a dust and waterprotector for the distributor plate, it might be. made of any suitablematerial other than metal, and in some arrangements it may be integralinstead of having'a detachable cover plate, or if the cover is used itmay be fastened to the rim of the housing by other than the means whichfasten the rim to the magneto frame.

Having thus described my invention, what I claim is:

1. In a multicylinder ignition generator, a generator frame having anopening, a distributor rotor arranged near said opening, a distributorplate having electrodes sequentially cooperative withthe distributorrotor, sparkplug cables electricallyconnected to the respectiveelectrodes, a housing covering the distributor plate and having aninturned flange, detachable fastening means fastening the distributorplate to said inturned flange interiorly of the housing, and otherdetachable fastening means fastening the housing to the generator frameexteriorly of the housing, whereby the distributor plate and its housingare removable from and attachable to the generator frame as a unit onlyand are attachable to and detachable from each other only when soremoved.

2. In a multicylinder ignition generator, a generator frame having anopening and at least one exterior lug, a' distributor rotor arrangednear said opening, a distributor plate having electrodes sequentiallycooperative with the distributor rotor and covering said opening,sparkplug cables electrically connected to the respective electrodes, ahousing covering the distributor plate and having an inturned flange,detachable fastening means fastening the distributor plate to theinturned flange of the housing interiorly of the housing, and otherdetachable fastening means fastening the housing to the exterior lug ofthe generator frame exteriorly of the housing, whereby the distributorplate and'its housing are removable from and attachable to the generatorframe as a unit only and when so attached the opening in the generatorframe is covered by the distributor plate, and are attachable to anddetachable from each other only when so removed.

3. In a multicylinder ignition generator, a generator frame having anopening, a distributor rotor arranged near said opening, a distributorplate having electrodes sequentially cooperative with the distributorrotor, sparkplug cables electrically connected to the respectiveelectrodes, a housing covering the distributor plate and having adetachable cover, detachable fastening means fastening the distributorplate to the housing interiorly of the housing, and other detachablefastening means each of which fastens the cover on the housing and alsofastens the housing to the generator frame exteriorly of the housing,whereby the distributor plate and housing with its cover are removablefrom and attachable to the generator frame as a unit only and areattachable to and detachable from each other only when so removed.

4. In a multicylinder ignition generator, a

generator frame of metal having an opening, a distributor rotor arrangednear said opening, a distributor plate having electrodes sequentiallycooperative with the distributor rotor and having a timing window,sparkplug cables electrically connected to the respectivevelectrodes, ametal housing covering the distributor plate and forming with thegenerator frame a radio shield for the generator, said housing having anopening in registry with the timing window and also having a movablemetal door arranged to seal the opening in the housing, detachablefastening means fastening the distributor plate to the housinginteriorly of the housing, and other detachable fastening meansfastening the housing to the generator frame exteriorly of the housingwith the timing windows in registry, whereby the distributor plate andits metal housing completing the radio shield of the generator areremovable from and attachable to the generator frame as a unit only andare attachable to and detachable from each other only when so removed.

WILLIAM D. CROCKER.

